渤海湾盆地黄骅坳陷古生界源内和源下油气成藏特征及有利区预测  

Hydrocarbon accumulation characteristics and favorable zones prediction in and under source of Paleozoic in Huanghua Depression,Bohai Bay Basin

作　　者：杨润泽 赵贤正[2] 刘海涛[1] 李宏军[2] 赵长毅[1] 蒲秀刚[2] YANG Runze;ZHAO Xianzheng;LIU Haitao;LI Hongjun;ZHAO Changyi;PU Xiugang(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;PetroChina Dagang Oilfield Company,Tianjin 300280,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油大港油田公司,天津300280

出　　处：《岩性油气藏》2023年第3期110-125,共16页Lithologic Reservoirs

基　　金：中石油科技部前瞻性项目“潜山内幕及复杂断块油气藏勘探评价技术研究”(编号:2021DJ0701);中石油勘探生产分公司前期项目“渤海湾盆地新层系新领域研究与有利区带评价”(编号:kt2021-06-02)联合资助。

摘　　要：煤系烃源岩是渤海湾盆地黄骅坳陷古生界含油气系统的主要烃源岩,源内和源下油气聚集机制和油气成藏过程不清。基于测井、录井、地震资料,结合烃源岩地球化学分析、储层岩心测试、包裹体测试、物理模拟实验等多种手段,探讨了渤海湾盆地黄骅坳陷古生界源内及源下油气聚集机制和成藏过程。研究结果表明:①黄骅坳陷古生界源内储层可有效聚集油气,紧邻的煤系地层烃源岩可优先对其供烃,稳定的构造背景使源内油气藏得到良好的保存。②研究区源下储层油气成藏的2个必要条件为:上部终止于煤系内部且下部连接奥陶系储层的断裂系统,且低角度断裂的油气输导效率更高;源储间存在大于10 MPa的压差,可为源下储层的油气成藏提供良好的动力。③研究区源内及源下油气藏具备早晚2期成藏、中期破坏的特征。中白垩世,低熟的煤系原油大量充注于储层中;白垩纪末期,地层的强烈抬升使古油藏遭受破坏或调整;新生代,随着烃源岩进一步成熟并生、排烃,形成了大量煤型气和轻质油油气藏。④研究区烃源岩有效充注范围内,储层相对优质、构造相对稳定的区域为源内勘探有利区,印支期逆冲断裂发育、受后期伸展作用改造较弱的区域为源下勘探有利区。Coal measure source rocks are the main source rocks of Paleozoic petroleum system in Huanghua Depression,Bohai Bay Basin.Hydrocarbon accumulation mechanism and accumulation process of the in-source and under-source reservoirs are not clear.Based on logging,well log and seismic data,combined with geochemical tests of source rocks,reservoir analysis and testing,inclusion tests,physical simulation experiment,the hydrocarbon accumulation mechanism and accumulation process in and under source of Paleozoic in Huanghua Depression were discussed.The results show that:(1)There is hydrocarbon accumulation in the in-source reservoirs of Paleozoic in Huanghua Depression,the in-source reservoirs are close to the source rocks,and the coal measure oil and gas can be charged preferentially.The stable structural background can make the in-source reservoirs well preserved.(2)Two necessary conditions are met for hydrocarbon accumulation in the Lower Ordovician,the fracture with upper end ending in coal measure and lower end connecting with Ordovician reservoirs,and the low angle fractures have higher transport efficiency.The source-reservoir pressure difference over 10 MPa is a good driving force for hydrocarbon accumulation.(3)The in-source and under-source reservoirs are characterized by accumulation in early and late stage and destroyed in middle stage.In Middle Cretaceous,low-mature crude oil was charged in large quantities.Strong tectonic uplift in Late Cretaceous caused the destruction or adjustment of the ancient oil reservoirs.In Cenozoic,with the further maturity of hydrocarbon source rocks,generation and expulsion of hydrocarbons,a large amount of coal gas and light oil accumulated and formed reservoirs.(4)The relatively stable areas with high-quality reservoirs developed within the range of hydrocarbon generation in the study area are favorable areas for in-source oil and gas exploration,while the areas where the Indosinian thrust faults developed and were weakly modified by later extension are favorable exploration area

关 键 词：煤系烃源岩 源内成藏 源下成藏 源储压差 油气聚集机制 古生界 黄骅坳陷 渤海湾盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]